package com.wpf.test03;

import java.util.ArrayList;
import java.util.Objects;

public class demo03 {
    public static void main(String[] args) {
        String s1 = null;
        String s2 = "he";
        System.out.println(s2.equals(s1));
        System.out.println(Objects.equals(s1,s2));

        Integer a = Integer.valueOf(12);
        System.out.println(a);

        ArrayList<Integer> list = new ArrayList<>();
        list.add(26);
        list.add(25);
        list.add(24);
        list.add(22);
        System.out.println(list);
        String rs = a.toString();
        System.out.println(rs);
        System.out.println(rs + "1");

        String abs = "9999";
        int b = Integer.parseInt(abs);
        System.out.println(b + 1);

        int c = Integer.valueOf(abs);
        System.out.println(c + 9999);
    }
}
